"There's still some risk it could pass close to New Zealand and have some significant impacts, so it's definitely a system that needs to be watched carefully."
As the system had not even formed yet, he said trying to predict where it would hit was like "trying to decide where a cricket ball is going to go before the bowler has even bowled the ball".
With the impacts of the cyclone potentially hitting the day after Aucklanders were permitted to leave the city, Ford advised holidaymakers to keep an eye on the weather.
"Just to be aware that if the system does pass near New Zealand it will bring significant impacts to the North Island – it would pay to keep an eye on the news and the upcoming forecasts for the upcoming week."
Meanwhile, Auckland's overnight lows have made for muggy sleeping conditions.
An update from Weather Watch says daytime heat is being locked in by humid, cloudy conditions "like a big thick duvet", and some northern areas may not drop below 20C in the week ahead.
Ford said muggy conditions were expected to continue over the coming week.
"We've had a lot of high-pressure systems that have sat off to the east of the north island, and that's brought quite a lot of warm air from the sub-tropics.
"That's contributed to quite a lot of soggy weather over the North Island. In Wellington we've had quite a lot of low cloud, drizzly, humid and muggy weather.
"It's going to stay muggy and a bit difficult to sleep at times."
